Centerless bar grinder machine



G.- W. BINNS Er AL cNTEnLEss BAR GRINDER CHINE Filed April 6, 1939 8Sheets-Sheet. 1

INVENTOR.

1 @wud/071A ATTORNEY.

Aug- 13,1940. G. w. BINNS Er AL- -2'2' 11,685'

CENTERLES BAR GRINDER MACHINE n Filed April es, 1939 s shuts-sheet 2Aug. 13, 1940. s. w. BINNs Erm. 52,211,685

CENTERLESS BAR GRINDER MACHINE med April e, 1939 a shuts-shuts' Aug. 13,1940. G. w. BlNNs Er AL 2,211,635

CENTERLES BAR GRINDER MACHIN Filed April 6. 19259y 8 Shoots-SheetA 4 d 4v ATTORNEY.

' Ang-V13. 1940. G. WJBINNS Erm. 2,211,685

CENTERLESS BAR GR'INDER MACHINE Filed April 6, 1959 8 Shoots-Sheet 5INVENTOR. GEMMA/ZMS BY iw/PU/YJ -TORNEK mg. 122, wm G. w. BINNS ,fr2,211,685

n CENTERLESS BAR GRINDER MACHINE I Filed April 6, 1939 8 Sheets-Sheet 6ATTORNEY.

Patented Aug. 13, 1940 UNITEDJ STATES PATENT OFFICE 2,211,685 CENTERLESSBAR GRINDER `MACHINE of Ohio Application April 6, 1939, Serial N0.266,333

16 Claims.

This invention relates to machine tools and more particularly toimprovements in centerless grinding machines.

One of the objects of this invention is to provide an improvedcenterless grinder that will efficiently grind long bar stock.

Another object of this invention is to provide a centerless grinder inwhich the axis of the grinding throat may be work determined rather thanmachine determined.

Another object of this invention is to improve the method of feedingwork through a centerless grinder by reducing the work feeding load onthe regulating wheel; or, on the other hand, make it possible to feedheavier work pieces through the machine than would otherwise be possiblefor a given size of regulating wheel.

A further object of this invention is to contrive a centerless grinderin a manner to take advantage of gravity to assist feeding and rotatingwork during grinding.

A still further object of this invention is to provide improved meansfor adjustably supporting the abrasive wheels in a centerless grinder.

An additional object of this invention is to provide improved means forpresenting unfinished work to the machine and for removing finished Workafter being ground.

Other objects and advantages of the present invention should be readilyapparent by reference to the following specification, considered inconjunction with the accompanying drawings forming a part thereof and itis to ybe understood v i that any modifications may be made in the exactviewed on the line 3-3 of Figure 2.

Figure 4 is a section on the line 4 4 of Figure 3 showing the manner oftrunnioning the abrasive wheel supportsv for angularvadjustment in oneplane.

Figure 5 is a section taken on the line 5-5 of Figure 3 showing thefeeding mechanism for the grinding wheel.

Figure 6 is a detail section on the line 6-6 of Figure 2 showing theadjusting mechanism for the regula-ting wheel.

Figure 7 is a section on the line 1-1 of Figure 2, with parts brokenaway showing the details of the work supporting mechanism.

Figure 8 is a diagrammatic view showing the angular relationship of thegrinding wheels and" the work with respect to a horizontal plane.

Figure 9 is a diagram cf a-n electrical control circuit for angularadjustment of the abrasive wheel supports.

Figure 10 is a section on the line lill0 of Figure 6.

Figure 11 is an elevational view of the adjustable supporting means forthe Work guiding blade.

Figure 12 is aplan view of the structure shown in Figure 11.

Figure 13 is a section on the line \l 3--l3 of Figure 11.

Figure 14 is a section on the line |4-l4 of Figure 13.

Figure l5 is a view on the line I5--l5 of Figure 11.

Figure 16 is a sectional view showing optional power control means forangular adjustment of the grinding and regulating wheel supports.

Figure 17 is a detail view of the power shifting mechanism for theclutch shown in Figure 16.

Figure 18 is a view of the H-slot control switch for the circuit shownin Figure 9.

Conventional centerless grinding machinery consists of various toolingand machine elements which are circumferentially arranged to form agrinding throat through which a work piece is passed for stock removalpurposes. Certain of these elements, when energized, produce a complexIsystem of forces acting on the work piece, which system may be resolvedinto three components. The first component acts to hold the work intoengagement with a guide which maintains the work in parallel relation tothe axis of the throat during its passage therethrough.

The second component produces a feeding of the work through the throatat a substantially uniform rate. ,l

The third component causes rotation of the work'relative to the grindingwheel whereby the entire cylindrical surface of the work is presented tothe grinding wheel during passage of the work through the throat.

In a conventional centerless grinder the axis of the grinding throat ismachine-determined, in thesense that the various elements are relativelypositioned to form the throat and determine the axis thereof, while theforce system maintains the work in parallel alignment with that axiswhile causing helical feeding thereof through the throat.

More specifically, the elements making up the grinding throat comprise agrinding wheel, a regulating wheel and some form of work guiding blade.The direction of rotation of the grinding wheel is such as to force thework against the blade and also to impart a rotational component to thework.

This, in turn, forces the work against the face of the regulating wheel,developing sufficient friction that the regulating wheel may control therate of rotation of the work.

For practical wheel widths and considering that only line contact existsbetween the wheels and the work, it is apparent that the forcecomponents that can be developed have practical limitations, so thatwhen exceedingly long work is put through the machine, the normal forcecomponents are inadequate and inefficient for effecting the desiredrotation and axial feed of the work. Part of this is due to the factthat along work piece must be supported throughout its length in axialalignment with the portion of the work going through the grinding throatxand there is a certain amount of friction that must be overcome inrotating and moving the work with respect to these outboard supportingmeans.

Since long heavy work pieces impose such an additional load on thegrinding and regulating wheels, the chief purpose of this invention isto provide a machine in which gravity will act to provide assistinggravitational components that will aid in rotating and feeding the work.

It is proposed to accomplish these objects by providing a gravitycenterless grinder in which the abrasive wheels are so arranged that theportion of the work passing through the grinding throat rests entirelyon the regulating wheel, thereby utilizing gravity to increase thefriction between the work and the regulating wheel.

In addition, the work is supported throughout its length at a deniteangle with respect to a horizontal plane so as to produce agravitational feeding component on the work in a direction toward thegrinding throat.

Unlike conventional centerless grinders, the work supporting means fixesor determines the axis of the work, while the elements which go to makeup the grinding throat are adjusted to produce a grinding throat havingan axis co-incident with the axis of the work. It will be evident thatthis differs from the usual practice in which the grinding throat ismachine determined as explained supra while here the axis of thegrinding throat is work determined.

Referring to Figures 1 and 2 of the drawings, the reference numeral Iindicates in general the bed of the machine proper upon which theabrasive elements II and I2 are supported for rotation. To the left ofthe bed I0, as viewed in these figures, is the lead-in work supportwhich is indicated generally by the reference numeral I3 and whichserves to supply unfinished work to the machine; and to the right of thebed I0 is the lead-out work support, indicated generally by thereference numeral I4, which receives the 1inished work from the machine.

Since this machine is designed for grinding long bar work it will beapparent that at certain stages in the grinding operation, opposite endportions of a work piece will be resting on the respective outboardsupports, while an intermediate portion will be in the grinding throatof the machine. This is true to such an extent that the outboardsupports actually determine the feeding path of the work.

Since one of the objects of this invention is to employ gravity as anagent in assisting the movement of the Work, the` outboard supports havea work supporting surface which is arranged at an angle to a horizontalplane.

This angle, which may be known as Ilie gravity feed angle, has beencarefully chosen in conjunction with a rotating feed drum upon theperiphery of which the work is supported, so that the staticco-efficient of friction between the work and the drum is sufficient toprevent creepage of the work when the drum is stationary, but issufficiently reduced upon rotation of the drum to impart a feedingmovement to the work. Thus, thc feeding of the work is controlled bystarting or stopping rotation of the drum.

The lead-in work support I3 comprises a base I5 upon the top of which isformed horizontal guideways I6 for receivingl an adjustable triangularwork supporting carriage I1. The lead-out support I4 is similarlyconstructed, and comprises a base I8 having horizontal guideways I9 uponwhich slides a triangular-shaped work supporting carriage 20.

Referring to Figure 7, it will be noted that one of the guideways I9 isflat, while the other is a V-shaped guideway. The carriage is providedwith a series of flat rollers 2l which engage the fiat guideway` and aseries of V-shapcd rollers 22 which engage the V-shaped guideway. Bymeans of this construction, the carriage is capable of adjustment towardand from the grinding elements without changing the gravity feed angleof the work. This serves to elevate the axis of the work with respect tothe machine. The supports I5 and I8 may be moved with respect to thefloor to change the angle at which the Work crosses the wheels.

The carriage 20 is provided with a work supporting drum 23 which isjournaled in the carriage at 24 and 25, and supported at spacedintervals throughout its length by pairs of opposed rollers, such as 26and 21 indicated in Figure '1.

This prevents the drum from sagging at any point and maintains astraight linelcngitudinally of the drum for maintaining lih'e".':ontactwith a work piece, such as indicated by t.,e reference numeral 28. Thework piece ridesfonthe periphery of the drum and is held in apfosi-tion`substantially vertically over the center of -rotation of the drum bylateral guides. v

The lateral guides 29 on one side of the work piece are fixed to thecarriage and may consist of sections of angle iron. while the guides 3Don., the other side of the work piece are rerravablefor the purpose ofreleasing the work so that it 6U may roll by gravity onto the receivingrack 3I. The guides 30 a're pieces of plate attached to the ends of aseries of arms 32 which, in turn` are secured to an oscillatable shaft33. The shaft is provided with an operating crank 34 which is connectedby a piston rod 35 to a piston 36 contained in the cylinder 31. Thecylinder is pivotally supported at 38 to the carriage 20. By admittingfluid pressure, such as compressed air, to the upper end of cylinder 31the shaft 33 may be rotated a sufficient amount to remove the lateralguides 30 and thereby release the work for gravity movement onto thereceiving rack 3|.

The drum 23 is driven by an electric motor 39 which is supported on anend plate 40 depending from the carriage 20. The motor shaft 4| drivesthrough a worm and worm gear mounted in the housing 42, a pulley shaft43 which carries a pulley 44. This pulley is connected by suitablemotion transmitting means, such as the belt 45, to a second pulley 46mounted on the end of the drum 23. It will be noted that the mechanismfor rotating the drum and for actuating the removable guide are allmounted on the carriage 20 so that when the same is adjusted they willall move as a unit.

The carriage adjusting mechanism comprises-a pinion 41 which ,isrotatably mounted on the carriage in a'position to interengage a rack 48carried by the bed. The shaft 49 to which the pinion 41 is securedhas asuitably formed end 50 for receiving a socket wrench for actuation ofthe shaft and pinion.

The work supporting carriage I1 carries a similar mechanism foractuating the feed roll and operating the removable lateral guides. Thedifference is that the work supporting rack members 52 are inclinedtoward the feed roll as shown in-Figure 7 so that the lateral guides 30in this case serve to prevent work. from rolling onto the feed roll. aswellrusj acting as a lateral guide for the single 'work piece that is onthe of support.

roll. The carriage '1 is -also longitudinally adjustable with respect toits support i5 for purposes of providing access to the grinding wheelswhen they have to be changed.

In setting up the machine a long test bar is laid in the trough of -thetwo work carriages and the carriages adjusted until the axes of thetroughs are in proper alignment. This determines the axis of travel ofthe work through the grinding throat of the machine.

The elements of the machine which form the grinding throat consist ofthe grinding wheel Il, the opposed regulating wheel |2, and a workthrust blade which is indicated by the reference numeral 53 in Figure 3.

The grinding wheel is attached to the end of spindle 54 which isjournaled in the wheel'head 55. This head carries an electric motor 56which is connected by a belt and pulley drive, indicated generally bythe reference numeral 51 to the spindle 54. point support with the bedof the machine.

The axis 58, Figures 4 and 8, located at the rear of the wheel headterminates in two points As shown in Figure 4, one of the pointscomprises a universal joint which isfanchored to the bed I0 of themachine. This joint includes a plate 59 which is secured t'o the bed I0by suitable bolts 60 and provided with a vhemi-spherical seat 6|.v Theunderside of the support 55 carries a cooperating member 82 having ahemi-spherical face 83 which is held in contact with the seat 6| by ayieldable connection comprising a bolt 64 which is threaded in the bedI0 but has clearance passage through the member 62.` A spring 65surrounds the bolt 64 and is interposed between a member 68 which.

engages the member 62' and a washer 61 held in adjustable position by anut 88 threaded on the upper end of the bolt. In this manner the member88 resiliently holds the two parts of the universal joint incontactwhile permitting movement of the grinding wheel support 55 in the planeof axis 58, or for movement in a plane at right angles thereto, or aboutthe axis 58.

` At the other end of the axis 58 is a journal 69 which as shown inFigure 3, is supported in vtwo half bearings 10 and 1| which arelaterally The wheel head 55 has a threeadjustable with respect to theaxis 58 by means of a threaded bolt 12 and nut 13. The bolt passesthrough a block 14 which has a ilat face on one side by which it isguided on a plate 15, and a bevel face 16 onthe other side which engagesthe half bearing 1|. The bolt passes through the frame 11 of the machinebed and the nut 13 is threaded on the upper end of the bolt and bearsagainst the frame 11 through an intermediate washer 18.

In the normal position of the parts, the axis 58 and the axis of thegrinding wheel spindle 54 would lie in the same plane and parallel tothe inclined plane of movement of the work.

The third point of support ior the grinding wheel head is indicated inFigure 5 by the axis 19 of the elevating screw 80 located at the frontof the machine as shown in Figure l.

A line drawn through center 8| of the universal joint and passingthrough the center of the grinding wheel is perpendicular to the axis58. Therefore, a line 82 connecting the center 8| and axis 19 will notbe perpendicular to the axis 58. Rotation of the elevating screw willcause movement of the grinding wheel support about the axis 58, whileadjustment by the nut 13 will cause oscillation of the support about theaxis 82.

The elevating screw 80 is threaded in a nut 8|' which is supported on ahemi-spherical seat 82 carried by the bed I0 of the machine,` and heldagainst rotation by a key 83. A flange 84 formed on the upper end of thescrew supports a bevel gear 85 which is keyed at 86 to the screw. Abeveled pinion 81 intermeshes with the bevel gear and has an elongatedhub 88 which is journaled in a boss 89 formed on one side of a sleeve90. The wheel head 55 has a hemi-spherical seat 9| which rests on theheini-spherical .face 92 of a spider 93.

The weight of the grinding wheel head is transmitted through the spider93, an anti-friction bearing 94 and hub of the gear 95 to the shoulder84 of the elevating screw. Anti-friction needle bearings 95 areinterposed between the hub of the spider and a bearing 96 formed on theupper end of the elevating screw.

The spider has lateral extending trunnions 91 and 98 which are journaledin the sleeve 90 freely movable relative to the hub of the gear 85whereby the weight of the grinding wheel head can maintain all the partsin contact with one another. The pinion 81 has clutch teeth 99 which areengageable by clutch teeth |00 formed on the end of the manual operablecrank |0|` whereby upon engagement with the clutch teeth and rotation ofthe crank, the elevating screw 88 may be rotated relative to the nut 8|.The universal joint at 82 permits the elevating screw to oscillateduring upward and downward movement as determined by the grinding wheelhead while the universal joint comprising the surfaces 9| and 92 permitthe grinding Wheel head to oscillate about the axis 82 when the screw 12is adjusted.

-The regulating wheel |2 is supported on one end of a spindle |02,Figure 3, which is journaled in a support |03. The latter has athree-point contact with the bed I0 for adjustment in two planes. Thewheel is driven by an electric motor |04 supported on a bracket |05projecting from the rearof the support |03. An elongated shaft |06extends from the motor to a gear box |01 mounted on the support |03.

A second shaft |08 has one end journaled for free rotation in the end ofthe shaft |06 and the other end journaled in the support |03. The shaft|05 has a pinion |00 formed integrally on the end thereof and thispinion carries clutch teeth which are engageable by clutch teeth on ashiftable clutch member I splined on the end of shaft |09. When theseclutch teetlf. are engaged, the shaft, drives the shaft |08 directly.

The gear box contains a set of back gears ||2 and I I3 integral with ashaft |4. The large gear I I3 intermeshes with the pinion |09 and thepinion I I2 ititermeshes with a large gear ||5 supported for freerotation on the shaft |08. The gear ||5 carries clutch teeth on the facethereof for engagement by clutch teeth on the clutch member III fordriving the shaft |08 at a slower rate. Thus, the clutch member servesas a selector of two different rotational rates of the shaft |08.

A worm I I6 keyed to the shaft |08 intermeshes with a worm gear xed onthe spindle, |02 for transmitting rotation to the regulating wheel I2.The clutch I I is shifted by means of shifter fork IIB supported on ashifter rod ||9 that has a rack and pinion connection with a shaft |20.A manually operable crank |2| secured to the end of shaft |20 serves asmeans for shifting the clutch into either one of its two positions.

The regulating wheel support has an axis |22, Figures 4 and 8, at therear end of the machine which terminates in a universal joint indicatedgenerally by the reference numeral |23 which is similar in constructionto the universal joint which forms one point of the three-point supportof the grinding wheel head 55. The other end of the axis is in the formof a journal |24 which is rotatably supported in two half bearings |25and |25 as indicated in Figure 3. These two half bearings are laterallyadjustable as a unit by means of the rotatable nut |21 and elevatingscrew |28. The screw |28 carries a bevel block |29 which engages theunderside of the half bearing |26 for raising or lowering the end of theaxis |22. It will now be apparent that the regulating wheel support maybe moved about the universal joint |23 in a plane determined by the axis|22 to vary the plane of rotation of the regulating wheel.

The third point of support for the regulating wheel structure is shownin Figure 6, and this point of support lies on an axis |30 which isperpendicular to the axis |22. The structure shown in Figure 6constitutes an elevating mechanism for the regulating wheel and whenadjusted, the regulating wheel support moves about the axis |22. Thisstructure comprises a roller |3| which is journaled on a shaft |32carried by the bed ID of the machine. The periphery of the roller isconcave in cross section and a wedge |33 carried on the underside of thesupport |03 is similarly shaped so that when the support |03 isoscillatcd about the axis |30 no change in the height of the regulatingwheel will be effected.

The wedge |33 carries a nut |34 which is engaged by an adjusting screw|35 anti-frictionally journaled at |36 in a bracket |37 carried by thesupport |03. A manually operable hand wheel |38 is keyed to the end ofthe screw |35 for eiecting manual adjustment thereof;

It will be obvious that upon movement of the wedge |33 toward the rightas viewed in Figure 6, that the regulating wheel will be raised towardthe work, and upon movement in the other direction it will he retractedfrom the work.

In setting up the machine the two outboard work supports are relativelyadjusted and positioned to determine the axis that a work piece, such as28, will travel through the grinding throat of the machine. In order tounderstand the relative angular relationship of the grinding wheels andthe work, a graphical representation of the angular relationship of thedifferent planes in which the various parts move is presented in Figure8.

In this gure, the reference numeral |39 indicates a horizontal plane andthe reference numeral |40 indicates an inclined plane. The intersectionof the planes is indicated by the line |4I. The inclined plane |40 istheplane in which the work moves in its travel through the grindingthroat of the machine. The work, however, does not travel in the plane|40 along a path perpendicular to the element |4| which would be along apath indicated by the line |42, but at a small angle with respectthereto and represented by the line |43. The grinding wheel axis |44 andthe regulating wheel axis |45 are, however, arranged to lie parallel tothe line |42 with the result that the work crossesb0th wheel faces at asmall angle, varying from four to ten degrees and which is known as thefeed angle.

It will be noted from Figure 3 that the work piece 28 lies in front of aline |46 which connects the centers of rotation of the grinding andregulating wheels. This is for the purpose of making it possible for themachine to round up work with greater facility than would be possible ifthe work was closer to the line |46. It is desirable, of course, thateach wheel make line contact with the work throughout the width of thewheel, and in spite of the fact that the work crosses the periphery ofthe wheel at an angle thereto. In order to accomplish this, the truingtool is passed across the face of the grinding wheel along a pathindicated by the line |41 in Figure 8, which is substantially parallelin all respects to the axis of the work. The same thing is true of theregulating wheel with the result that both wheels will have a concaveperiphery when viewed in cross section.

Thus, each abrasive wheel is trued to provide a straight line of Contactwhich extends diagonally across the face of the wheel. Since there isapt to be a variation between the angle of inclination of the work andthe angle of inclination of the contact line on the wheels, theadjustment of the wheels about the axes 82 and |30 is provided wherebyit becomes possible by adjusting the plane of rotation of the wheels tobring the line of contact on the wheels into parallelism with the axisof workl travel. By providing the foregoing adjustments for thetwo-wheel supports it becomes possible to move either wheel toward andfrom the axis of the work to compensate for wear and other operatingpurposes, and to adjust the planes of rotation of the wheels toestablish line contact with the work in such an angular relation that arotative component will be exertedfon the work to cause axial feedthereof, which component 1s assisted by the gravitational feed componentresulting from the inclination of the work. A

The two wheels may thus be adjusted to form a grinding throat which hasan axis that is determined by the position of the axis of the work. Athird element is necessary, however, to complete the formation of thegrinding throat and this element is the work guiding blade 53 which issupport ed on the bed of the machine in the manner shown in Figure 11. i

Referring now to Figures 11 to 15 inclusive, the blade 53 is supportedfor adjustment in a plurality of directions to compensate for such itemsas change in work diameter, angle of work feed, or wear of the bladeitself. As shown in Figure 11, lthe blade 53 is attached to a supportingplate |48. The plate |48 is supported on the top o1 an angle bracket |49and secured thereto by a pair of clamping plates |50 and |5|.

The bolts |52 which pass through the clamping plate |50 and are threadedinto the angle bracket |49 pass through enlarged holes |53 formed on theplate 48. Similarly, the clamping bolts |54 which pass through the plate|5| and are threaded in the top of the angle bracket, also pass vthroughenlarged holes |55 formed in the plate |48. 'I'hese enlarged holes`permit the plate |48 to be universally adjusted in the plane of the topof the angle bracket 49. One of these adjustments is effected by twobolts |56 and |51, whichpass through elongated holes |58 and |59 formedin a side plate |60, and are threaded into the plate |48. The side plate|60 also carries a threaded studx |6| which is threaded into the sideplate midway between the bolts |56 and |51 and engages the side of plate|48 to act as a pivot for angular adjustment of the plate |48.

The stud |6| has a hexagonal shaped socket |62 formed in the end thereofas shown in Figure 11 for receiving a wrench whereby the stud may beadjusted to adjust the blade 53 longitudinally of the work. A lock nut|63 is threaded on the stud for locking it in any given position. Afterthe longitudinal adjustment of the blade 53 has been effected, the'bolts|56 and |51 are reversely rotated to effect the desired angularadjustment of the blade. These two adjustments are effected while thebolts |52 and |54 are loose and may be effected regardless of theposition of the blade toward or from the axis of the grinding throat dueto the elongatedslots |58 and |59 and the enlarged holes formed in thesupporting plate |48. This adjustment toward and from the grindingthroat may be effected by a pair of screws |64 and |65 threadedin therear of the plate |48 but, as a practical matter, after the necessaryadjustments have been made by the means carried by the side plate |60,the bolts |64 and 65 are rotated in a direction to engage the solidsupport |66 to thus serve as backing up bolts for the plate |48. Thelock nuts |61 are then tightened, after which the bolts |52 and |54 aretightened to secure the blade 53 against movement in two directions.

The side plate |60 is secured to the angle bracket |49 by a pair oflocking screws |68 which pass through elongated slots in the side plate|60, the elongated slots extending in a direction whereby the plate |48and attached side plate |60 may be elevated with respect to the anglebracket so that shim plates of different thicknesses' may be insertedbetween the plate 48 and the top of the bracket for effecting majorvertical adjustments of the blade 53..

In addition to the adjustments which may be effected by the meanscarried by the top of the angle bracket, the bracket itself is supportedfor rotational adjustment about a boss |69 and for vertical adjustmentby a cam |10 shown in Figure 13.

The boss |68, as shown in Figure 14, is carried by a slide |1| which isV-guided in the fixed support |12. The bracket |49 carries a clampingbolt |13 which passes through the center of the boss |69 and is keyedthereto by a key |14. The bolt 13 has a threaded end |15 for receiving aclamping nut |16, the clamping nut having a ange 11 which engages thesolid support |12. The bolt |13 passes through an elongated slot |18formed in the solid support |12 whereby the angle bracket may bevertically adjusted. The key serves to hold the bolt |13 againstrotation during rotation of the locking nut |16.

Vertical adjustment is effected by the cam |10 which engages the beveledface |19 formed on the bottom of the slide |1| by rotating screw |80which is held against axial movement in the iixed support |12 andthreaded in the cam member |10. Thus, when the locking bolt |16 isloosened and the screw rotated, the slide I 1| will be raised or loweredto effect raising or lowering oi the work guiding blade 53.

The angular adjustment of the bracket |49 is effected by an adjustingscrew |8| which, as shown in Figure 15, is carried by the bracket |49for engagement with a xed stop |82. A second adjusting screw |83 isthreaded in the plate |84 fixed to the support |12 whereby rotation ofthe screw in one direction will effect counterclockwise rotation of thebracket |49, and rotation of the screw |8| in the same direction willeffect clockwise rotation of the bracket |49. When adjustment is to beeffected one of these screws is backed oif and the other advanced toeffect the necessary adjustment. The rst screw is then tightened to lockthe parts.

The blade 53 is thus capable of angular adjustment with'respect to botha vertical and horizontal plane, of major vertical adjustments by shimplates, of minor ver'if *.l adjustments by the cam |10, and universaladjustment in a horizontal plane.

The means for adjusting the planes of rotation of the grinding andregulating wheels are located at the rear of the machinevas shown inFigure 3, and since this is a rather inconvenient location, means havebeen provided as shown in Figures 9, 16, 17 and 18 whereby thisadjustment may be power effected and conveniently controlled from thefront of the machine.

The power adjusting mechanism is more particularly shownin Figure 16 andcomprises a -gear box |85 which is mounted on top of the frame 11 and inwhich is journaled a worm |86 driven by a motor |81. The worm |86rotates a worm gear |88 which, in turn. drives a pair of intermeshingspur gears |89 ane |90. The spur gear |90 is keyed to a shaft |9| whichalso has .keyed thereto a shiftable clutch member |92. The clutch memberwhen shifted upward, las viewed in Figure 16, intermeshes with clutchteeth formed on the face of spur gear |93 and when shifted downwardintermeshes with clutch teeth formed on the face of spur gear |94. Thegear |93 driven through idler |95, a spur gear |96 which is pinned to anelongated shaft |91.

This shaft has a squared end |98 which interts in a square socket formedin the upper end of nut |21. The spur gear |94 meshes directly with aspur gear |99 which has a threaded connection with the end of screw 12.It will now be seen that when the clutch member |92 is shifted upwardthe plane of rotation of the regulating wheel will be angularly adjustedthrough axial movement of bolt |28 and when shifted downward the planeof rotation of the grinding wheel will be similarly effected through thescrew 12.

The clutch member |92 is provided with a shifter fork 200 which ispivoted at 20| as shown in Figure 1'7 and connected to armature 202 and203 of operating solenoids 202 and 205 respectively.

The electric motor |81 is a three-phase reversible motor and as shown inFigure 9 a switch 200 is provided for connecting the motor to the powermains 201, 208 and 209 for effecting one direction of rotation, and asecond switch 2|0 is provided for connecting the motor in a reverserelation to the power mains for effecting an opposite direction ofrotation thereof.

The switch member 20B is operated by a closing coil 2|| while the switch2|0 is operated by a closing coil 2|2. The ends 2|3 and 2|4 of theclosing coils respectively are connected to the power main 201 throughline 2|5, thermal relays 2|0 and 2|?, and branch line 2|0. The otherends of the closing coils are connected for control by an H-slot controllever 2|9 which may be mounted on a pedestal 220 located at the front ofthe machine as shown in Figure 2. This lever is shiftable into fourdii-ferent positions for actuating limit switches 22|, 222, 223 and 224which are located with respect to the lever in the positions shown inFigure 18, Each limit switch determines a direction of rotation of themotor |81, and also actuation of one of the solenoids 204 or 205.

Thus, when the lever is thrown to a given position, it starts rotationof the motor |81 in a determined direction and then shifts the clutchmember |02 into a denite position for connecting the motor foradjustment of one or the other of the abrasive wheels. The limit switch22| has a pair of contacts 225 and 220 which when closed connect thepower main 20S to one end of the closing coil 2|2 through line 221, theother end of the closing coil being connected as previously mentioned topower main 201. The switch also has a second pair of contacts 220 and229 which when closed connect the power main 209 through lines 230 and23| to the end of solenoid 204, the other end being permanentlyconnected through line 232 to power main 201. If the lever 2|9 isshifted downward it will close limit switch 224 and thereby interconnectcontacts 233 and 230 which are connected in parallel with the contacts228 and 229 whereby the clutch solenoid 200 will still remain energized.

At the same time, however, contacts 235 and 236 will be interconnected,thereby energizing the starting coil 2H and deenergizing starting coil2|2 due to the opening of limit switch 22|. In a similar manner thelimit switch 222 has a first pair of contacts 231 and 230 which whenclosed will energize the starting coil 2|2; and a pair of contacts 239and 200 which when closed will energize solenoid 205.

Limit switch 223 has a pair of contacts 20| and 202 which when closedenergize starting coil 2|| and a second pair of contacts 203 and 202,which energize solenoid 205. It will thus be apparent that by use ofcontrol lever 2|0 angular adjustment of the plane of rotation of eitherabrasive wheel may be effected and in either a clockwise or acounterclockwise direction from the iront of the machine.

The pedestal 220 also carries the push button controls 205 and 200 forthe wheel motors 56 and |00, and the air valves 201 and 208 forcontrolling the lifting of the work guides whereby a work piece maygravitate into the lead-in work drum or gravitate of of the lead-outwork drum after it has cleared the machine.

There has thus been provided an improved centerless bar grinding machinein which the axis of movement of the work is positively determined bymeans outside of the grinding throat, and means are provided foradjusting the grinding wheel, regulating wheel and work rest blade in amanner to cause them to converge about the work in a manner to form agrinding throat having an axis co-incidental with the axis of the work;and in which the feed axis of the work is inclined to a horizontal planeto thereby impart a, gravitational feed component thereto in a manner toassist the feed component developed in the grinding throat by thegrinding and regulating wheels.

We claim:

l. In a centerless grinding machine having a grinding wheel, aregulating wheel and a work guiding blade forming a grinding throathaving an axis lying in a plane inclined to the horizontal, thecombination of a three-point support for the grinding wheel comprisingan anchored universal joint, a pivoted trunnion having an axis passingthrough said universal joint, elevating means connected to the grindingwheel support and lying in an axis which passes through a central planeof the wheel and said universal joint, means to oscillate the supportabout one of said axes to change the plane of rotation of the wheel, andmeans to actuate said elevating means to feed the grinding wheel towardor from the work.

2. In a centerless grinding machine having a grinding wheel, thecombination with means independent of the machine for. determining thepath of movement of a work piece past the grinding wheel, thecombination of means for supporting a regulating wheel on the side ofthe work opposite the grinding wheel, said supporting means having threepoints of support lying on intersecting axes, one of said axes passingthrough a central plane of the wheel. means to oscillate said supportingmeans about one of' said axes to move the regulating wheel intoperipheral contact with the work, and means to oscillate said supportingmeans about the other axes to align the line of contact of the face ofthe regulating wheel parallel to the axis of feed of the work.

3.,In a centerless grinding machine, having means for guiding a workpiece through the machine in a plane inclined to a horizontal plane. thecombination of a grinding wheel, a regulating wheel` means forsupporting said wheels for i.

rotation about axes lying in a plane perpendicular to the line ofintersection between the horizontal and inclined planes, the path ofmovement of the work being angularly related to said line ofintersection, said wheels being trued to provide a straight line ofcontact parallel to the path of movement of the work. means to move therespective wheels into contact with the work andh the angle of the bladein a second plane at right angles to the first-named plane.

In a grinding machine having a support, and spaced grinding andregulating wheels mounted on said support, the combination of a workguiding blade, means t0 support the blade on said support andintermediate said wheels including an angle bracket, a dovetailed slide'reciprocably mounted on the support, said slide carrying a bosssupporting the angle bracketfor swivel ad- J'ustment, a .side platecarried by the angle bracket, a supporting plate for said blade mountedon the angle bracket, means carried by the side plate for effectingangular adjustment of the supporting plate Ito align the blade parallelto the travel of the work, and means to positively lock the,blade insaid position 6. In a centerless grinder having a supporting frame and apair of opposed -grinding-and regulating wheels, the combination ofmeans for supporting the wheels on said frame for angular adjustment oftheir planes of rotation, pairs of cooperating threaded members foreiecting angular adjustment of the respective wheels, a power operablemember, and means to selectively connect said member for effectingrelative movement between themembers of one of said pairs of threadedmembers to eiect said angular adjustment.

7. In a centerless grinder having a supporting frame and a pair ofopposed grinding and regulating wheels, the combination of meansforsupporting the wheels on said frame for angular adjustment of theirplanes of rotation, pairs of cooperating threaded members for effectingthe respective angular adjustments, a power operable member, means toselectively connect said power member for effecting relative movementbetween the members of one of said pairs of threaded members to eiectsaid angularadjustment, and means to change the direction of saidrelative movement 8. In a centerless grinder having a supporting frame,a pair of opposed grinding and regulating wheels mounted thereon, meansfory supporting said wheels on the frame for angular adjust-ment oftheir planes of rotation including a pair of cooperating threadedmembers associated with each wheel for effecting adjustment thereof, aprime mover, motion transmitting trains extending to each pair ofthreaded members, a powerl operable selector for selectively connectingthe prime mover to either train, a control member, and means operablethereby for determining the direction of rotation of said prime moverand for actuating saidl selector.

9. In a centerless grinder having a grinding wheel anda regulatingwheel, the combination of an adjusting mechanism for each wheel forangularly changing the plane of rotation thereof, a power trainextending to each mechanism.

a prime mover, an electrically operated selectm` l clutch for connectingthe prime mover to said trains, a reverser for said prime mover, acommon control for said reversing means and for said clutch operatingmeans, said control having a neutral position, and a plurality of otherpositions for determining the adjusting mechanism to be actuated and itsdirection of actuation,

10. A grinding machine having a bed, a grindlng wheel head supported atthree points on the bed, said three points determining a plane inclinedto the horizontal, a regulating wheel'supportsupported at three pointson the bed, said three points determining a plane inclined to the ymovercarried by the regulating wheel support lor driving the regulatingwheel, means external of the bed for guiding work past said wheels at aninclination toa horizontal plane and in an angular `relation-to the axisof rotationof said wheels, means to adjusv one point of support oi' boththe grinding'wheel and the regulating wheel to advance the wheelstowardthe work, and additional means for adjusting a second point ofsupport of both of said wheels for angularly adjusting the planes ofrotation thereof to establish a line of contact with the Work parallelto the axis of movement thereof.

11. In a long bar centerless grinder, the combination with opposedgrinding and regulating wheels and a. work guiding blade adapted to forma grinding throat, of a lead-in work support and a lead-out work supportmounted on opposite sides of said grinding throat, rotatable drumssupported on each work support, a storage rack associated with thelead-in work support and inclined toward the drum whereby work will moveby gravity from the rack to the drum, power operated means forcontrolling movement of the work onto the drum, means to rotate the drumto cause axial feeding of the Work past the Agrinding wheel, andadditional means for controlling movement of the work from the receivingdrum to the receiving rack.

12. In a long bar centerless grinder, the combination with opposedgrinding and regulating Awheels and a work guiding blade adapted to forma grinding throat, of a lead-in work support and a lead-out work supportmounted on opposite sides of said grinding throat, rotatable drumssupported on the work supports, a storage rack associated with thelead-in work support and inclined toward the drum carried therebywhereby work will move by gravity from the rack to the drum, poweroperated means for controlling movement of the work onto the drum, meansto rotate the drum to cause axial feeding of the work, additional meansfor controlling movement of the work from the receiving drum to thereceiving rack, and means to adjust said work supports to raise or lowerthe axis of the Work with respectto the supporting frame of the grindingwheel.

13. A machine of the character described, including a central Wheelsupporting portion and lateral work supporting members and said lateralmembers having parallel ways disposed at different elevations, andsubstantially triangular work piece supporting members slidably mountedon said ways for movement in a direction toward and from the wheelsupporting section, and work supporting devices mounted on said membersand adjustable into axiall alignment for support of an elongated workpiece during its passage through the wheels,

14. A machine of the character described, including a central wheelsupporting portion and lateral work supporting members and said lateralmembers having parallel Ways disposed at different elevations, andsubstantially triangular work piece supporting members slidably mountedon said ways for movement in a direction toward and from the wheelsupporting section, and Work supporting devices mounted on said membersand adjustable into axial alignment for support of an l elongatedyworkpiece during its passage throlngh mined axis for the work piece and anoverlying grinding wheel, and means for effecting individual positioningmovements of the respective Wheels with respect to the intermediatesupport determined Work piece axis.

15. A machine of the character described, including a central wheelsupporting portion and lateral work supporting members and said lateralmembers having parallel ways disposed at different elevations, andsubstantially triangular work piece supporting members slidably mountedon said Ways for movement in a direction toward and from the wheelsupporting section, and work supporting devices mounted on said membersand adjustable into axial alignment for support of an elongated workpiece during its passage through the wheels, said wheels including anrst regulating wheel member s'ubtending,the support determined axis forthe Work piece and an overlying grinding wheel, means for effectingindividual positioning movements of the' respective wheels with respectto the intermediate support determined work piece axis, and anindependently adjustable work rest member carried by the g5 wneelsupporting unit for movement in a direction toward and away from thesaid support determined work piece axis, whereby accurate three-pointengagement of a work piece between grinding and regulating Wheels andsupport blade may be effected without distortion of the work piece fromits support-determined axis.

16. In a machine of the character described including a work supportingmember for determining the axis of a work piece during performance of acenterless grinding operation thereon, abutment members disposedadjacent said work supporting member for preventing axial deflection ofa Work piece mounted thereon, a work supporting rack adjacent saidpotential work supporting member, a plurality of retractable lateralwork engaging abutments and means for selectively shifting saidabutments into retracted position permitting lateral interchange o1 awork piece between the rack and Work support or into projected position,retaining the work piece on the support in opposition to themst-mentioned abutments to cooperate therewith in preventing said axialdeflection of the work.

GEORGE W. BINNS. BERNARD A. KEARNS.

